Intersection · Analytics × mass error (ppm)

Analytics topics tagged mass error (ppm)

Topics in Analytics carrying the tag mass error (ppm). Difference between measured and theoretical mass, expressed in parts per million.

23 topics

Topic	Participants	Replies	Views	Activity
About the Mass spectrometry category LC-MS high-resolution MS mass error (ppm) Pinned Wiki LC-MS and high-resolution MS, charge states, mass accuracy in ppm, and what identity confirmation does and does not establish. This post is a community wiki: any member at trust level 3 or above can edit it,…	+5	9	19k	6h
Isotope patterns and why the monoisotopic peak is not the tallest — does this still hold? charge states counter-ion content high-resolution MS mass error (ppm) Solved Isotope patterns and why the monoisotopic peak is not the tallest — does this still hold? — that is the question, and I have not found it answered plainly anywhere I have looked. Working through the identity…		2	4.6k	7h
Second pass at: What a 2 ppm match establishes, and what it does not MALDI-TOF mass error (ppm) counter-ion content high-resolution MS Second pass at: What a 2 ppm match establishes, and what it does not — setting out what I have, and where I think it stops being reliable. Working through the identity arithmetic and I would like it checked.…	+44	49	8.1k	1d
Mass error in ppm: the arithmetic and the caveat — a second dataset counter-ion content mass error (ppm) charge states LC-MS Solved On the subject in the title: Mass error in ppm: the arithmetic and the caveat — a second dataset Working notes rather than a conclusion. Working through the identity arithmetic and I would like it checked.…	+20	24	1.7k	1d
Adducts: sodium, potassium, and the peak you did not expect — does this still hold? high-resolution MS charge states mass error (ppm) MALDI-TOF Solved Asking directly, because I could not find a straight answer: Adducts: sodium, potassium, and the peak you did not expect — does this still hold? Posting the method first, because I know what the first three…	+113	119	1.7k	3mo
Charge states for a 4 kDa peptide, worked through — the long version LC-MS high-resolution MS mass error (ppm) Charge states for a 4 kDa peptide, worked through — the long version Writing it up because I had to work it out twice and would rather nobody else did. Working through the identity arithmetic and I would like…		2	293	3mo
Second pass at: Counter-ion content and its effect on measured mass mass error (ppm) counter-ion content MALDI-TOF charge states Solved Second pass at: Counter-ion content and its effect on measured mass Writing it up because I had to work it out twice and would rather nobody else did. Working through the identity arithmetic and I would like…		4	16k	4mo
Second pass at: MALDI versus ESI for a quick identity check MALDI-TOF mass error (ppm) high-resolution MS counter-ion content Solved Second pass at: MALDI versus ESI for a quick identity check Writing it up because I had to work it out twice and would rather nobody else did. Working through the identity arithmetic and I would like it…		2	18k	7mo
What a 2 ppm match establishes, and what it does not high-resolution MS charge states LC-MS MALDI-TOF What a 2 ppm match establishes, and what it does not — that is the question, and I have not found it answered plainly anywhere I have looked. Working through the identity arithmetic and I would like it…	+56	60	5.2k	9mo
Deconvolution of a multiply charged envelope MALDI-TOF charge states mass error (ppm) counter-ion content Closed Deconvolution of a multiply charged envelope — setting out what I have, and where I think it stops being reliable. Working through the identity arithmetic and I would like it checked. tirzepatide has a…		2	63	10mo
Coming back to: Oxidation and deamidation mass shifts, tabulated LC-MS charge states MALDI-TOF high-resolution MS Oxidation and deamidation mass shifts, tabulated — setting out what I have, and where I think it stops being reliable. Working through the identity arithmetic and I would like it checked. retatrutide has a…	+34	38	4.8k	10mo
MALDI versus ESI for a quick identity check high-resolution MS charge states mass error (ppm) MALDI-TOF Closed On the subject in the title: MALDI versus ESI for a quick identity check Working notes rather than a conclusion. Working through the identity arithmetic and I would like it checked. tirzepatide has a…		2	2k	11mo
Distinguishing a deletion sequence by mass alone — the long version high-resolution MS mass error (ppm) charge states MALDI-TOF On the subject in the title: Distinguishing a deletion sequence by mass alone — the long version Working notes rather than a conclusion. I would like to understand what this number means before I repeat it…	+38	44	60k	11mo
Counter-ion content and its effect on measured mass high-resolution MS charge states MALDI-TOF LC-MS Solved On the subject in the title: Counter-ion content and its effect on measured mass Working notes rather than a conclusion. Working through the identity arithmetic and I would like it checked. retatrutide has a…	+100	108	45k	12mo
Reading an MS report that only gives you a single number counter-ion content mass error (ppm) charge states On the subject in the title: Reading an MS report that only gives you a single number Working notes rather than a conclusion. I would like to understand what this number means before I repeat it anywhere. A…	+100	113	48k	13mo
Adducts: sodium, potassium, and the peak you did not expect LC-MS MALDI-TOF mass error (ppm) Wiki Adducts: sodium, potassium, and the peak you did not expect Writing it up because I had to work it out twice and would rather nobody else did. I would like to understand what this number means before I repeat…	+70	77	3.5k	15mo
Oxidation and deamidation mass shifts, tabulated counter-ion content charge states LC-MS mass error (ppm) Solved Posting this under the heading it deserves: Oxidation and deamidation mass shifts, tabulated Everything below is what sits behind that. Working through the identity arithmetic and I would like it checked.…	+67	76	21k	16mo
Charge states for a 4 kDa peptide, worked through high-resolution MS counter-ion content charge states LC-MS Solved On the subject in the title: Charge states for a 4 kDa peptide, worked through Working notes rather than a conclusion. Working through the identity arithmetic and I would like it checked. retatrutide has a…	+124	146	15k	16mo
Why mass spectrometry cannot tell you about an epimer LC-MS mass error (ppm) high-resolution MS charge states Why mass spectrometry cannot tell you about an epimer I have a specific reason for asking rather than idle curiosity, and the context is below. Posting the method first, because I know what the first three…	+75	82	4k	17mo
Isotope patterns and why the monoisotopic peak is not the tallest LC-MS MALDI-TOF mass error (ppm) high-resolution MS Isotope patterns and why the monoisotopic peak is not the tallest — setting out what I have, and where I think it stops being reliable. Working through the identity arithmetic and I would like it checked.…	+12	16	7.5k	17mo
Distinguishing a deletion sequence by mass alone mass error (ppm) high-resolution MS LC-MS MALDI-TOF Solved Distinguishing a deletion sequence by mass alone Writing it up because I had to work it out twice and would rather nobody else did. Working through the identity arithmetic and I would like it checked.…	+121	129	25k	17mo
Reading an MS report that only gives you a single number — the long version mass error (ppm) counter-ion content LC-MS high-resolution MS Reading an MS report that only gives you a single number — the long version — setting out what I have, and where I think it stops being reliable. I would like to understand what this number means before I…		2	47k	18mo
High-resolution MS on aggregates and what it can see — one year on LC-MS counter-ion content MALDI-TOF charge states Solved High-resolution MS on aggregates and what it can see — one year on Writing it up because I had to work it out twice and would rather nobody else did. Working through the identity arithmetic and I would like…	+54	58	1.2k	23mo

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